I think #15 is different diameters at each end; or is that 12? It is also very close to the pulley, right? The SS sets eliminated that rubber-near-the-pulley issue; and the stock two diameter hose is not an off-the-shelf at NAPA part, either. I've got 2511 up in the air right now; I'll slide under a take a photo or two later tonight.
Larry
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